Pilot burner arrangement



Jan. 242 1939. T E, PHARES 2,144,894

PILOT BURNER ARRANGEMENT Filedv March 27, 193s PHE Patented Jan. 24,1939 PATENT oEFIcE PILOT BURNER ARRANGEMENT Thomas Esta Phares,Shelbyville, Ind., assigner to Chambers Corporation, Shelbyville, Ind.,a

corporation of Indiana Application March 27, 1936, Serial No. 71,113

1 Claim.

My invention relates to pilot lights used on gas-burning equipment, suchas gas-ranges, and particularly to a pilot-light arrangement of theexplosion type. In this type of pilot-light, a supply of gas from theburner is mixed with air to form an explosive mixture and conveyedthrough a tube to the pilot burner. When the explosive mixture reachesthe pilot burner, the gas within the tube explodes and creates a. flamewhich serves to ignite the burner.

I have found that equipment of this kind now available, while it may besatisfactory for gas of one of the three kinds no-w being used (natural,artificial, and bottled) will not operate satisfactorily with gases ofother kinds due largely to the difference in proportions necessary tocreate an explosive mixture. It is the object of my invention to applyto pilot-light equipment of the explosive type means which will adaptthe equipment for use in connection with burners burning different kindsof gas.

In carrying out my invention, I provide means for varying the eiectivearea of the opening through which air is admitted to the explosion tube.In the preferred form of my invention, where a jet of gas enters theexplosion tube through an opening in the lower wall thereof and servesalso to induce a flow of air through such opening, my inventionconveniently takes the form of a sleeve which surrounds the explosiontube and which by longitudinal adjustment thereon varies the effectivesize of the opening in the wall of the tube.

The accompanying drawing illustrates my invention: Fig. 1 is a plan Viewof a portion of a gas range showing a single burner and the pilotlightequipment associated therewith; Fig. 2 is a fragmental view similar toFig. 1 with parts of the explosion tube broken away to show inhorizontal section; and Fig. 3 is a vertical section on the line 3-3 ofFig. 2.

In the gas range, a portion of which is shown in Fig. 1, the mainburners are supplied with gas from amanifold I0. Only one burner I I isshown in Fig. l, but it will be understood that any desired number ofburners may be embodied, each being supplied with gas from the manifoldI under control of a valve I2.

Also supplied with gas from the manifold I0 is a pilot burner I3, thesupply of gas to which may be regulated by a valve I4.

The pilot burner I3 is conveniently centrally located with respect tothe burners of the stove, and an explosion tube extends from each ofsuch burners to a point adjacent the pilot burner. As

indicated in the drawing, each explosion tube is formed of twotelescoping parts I5 and I6 in order that the tube may readily beadapted to ranges of different dimensions. Near its outer end, each ofthe tube-parts I6 is provided with a downwardly projecting boss I1 thelo-wer end of which is conical in shape to conform to a tapered holeprovided in the upper wall of the associated burner II. Thus, the outerend of each of the explosion tubes is supported on its associatedburner, while the inner end receives support from the housing usuallyprovided for the pilot burner.

Both ends of each explosion tube are open; and, in addition, thetube-part I6 is provided in its lower surface with an opening I8 theouter end of which is located adjacent the boss II. The boss II isprovided with a downwardly opening recess with which there communicatesa discharge port I9 adapted to direct from the burner I I a jet of gaswhich rises obliquely upwardly toward the opening I8.

The construction as so far described is old. In operation, the pilotburner burns continually. When any of the valves I2 is opened, gas issupplied tothe associated burner II. On its way to the burner II, thisgas becomes mixed with sufcient primary air to produce a satisfactorilycombustible mixture which is too rich in gas tobe explosive. Some of thecombustible mixture of gas and air is discharged through the port I9 andrises through the opening I8 into the interior of the explosion tube.The jet of gas emerging from the port I9 induces an inward flow of airthrough the opening I8, the opening I8 being of such a size that theamount of air admitted will create an explosive mixture within theexplosion tube. When this explosive mixture lls the explosion tube andemerges from the inner end thereof adjacent the pilot burner I3, it isignited; and, when the resultant burst of flame emerges from the outerend of the explosion tube, it ignites the gas emerging from the ports ofthe burner II.

I nd that in order for a device oi this kind to operate satisfactorilythe effective area of the opening I8 will differ materially with thetype of gas used. To render the pilot-burner equipment adaptable for usewith gases of different kinds, I therefore provide means for adjustingthe eiective size of the opening I8.

In the device illustrated in the drawing, the means employed for varyingthe size of the opening I8 takes the form of a sleeve 28 which surroundsthe tube-part I6 and is longitudinally adjustablethereon. To aid indeecting gas and air into the explosion tube, the lower Wall of thesleeve 2D, at its outer end, may be bent downwardly to provide aninwardly and upwardly sloping tongue 2 I, as indicated in Fig. 3.

It will be apparent that by longitudinal adjustment of the sleeve 20upon the tube I6 the effective area of the opening I8 may be regulatedto Vary the amount of air whichis admitted into the explosion tube withgas from the port I9. It thus becomes possible to produce in theexplosion tube and explosive mixture of gas and air, irrespective of thetype of gas supplied to the burner I I. For gases in which the explosivemixture is relatively lean, the sleeve 20 is moved inwardly to increasethe eiective area of the opening I8 thus increasing the quantity of airwhich enters the explosion tube with the gas. If the gas supplied to theburner I I is one which requires a relatively small quantity of air toproduce an explosive mixture, the sleeve 20 is moved outwardly todecrease the effective area of the opening I8 and to decreasecorrespondingly the amount of air which enters the explosion tube: withthe gas.

- I claim as my invention:

In combination, a main gas burner and a pilot burner remote therefrom,said main burner being provided in its upper wall with an auxiliaryport, an explosive ignition tube extending from said main burner to saidpilot burner and having in its lower wall adjacent said auxiliary portan opening for admission of gas from said port and of air, and a. sleeveslidable upon said explosion tube to Vary the effective size of saidopening, the lower wall of said sleeve extending obliquely downwardtoward said port.

THOMAS ESTA PHARES.

